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Cecil Moore · August 29th 06, 02:15 AM posted to rec.radio.amateur.antenna

wrote:
Send out a pulse into your one second misterminated line
via your ideal autotuner. Wait half a second. FREEZE! Now run the
film backward while obeying the rules of your autotuner. The pulse
doesn't go back into the source. It bounces. What's up?

I certainly didn't say that. The steady-state voltage and
current component values have to exist for 100% destructive
interference to occur at a Z0-match. On the source side of
the Z0-match, in order to eliminate the reflected energy
wave, two reflected wave components are required to be
traveling in the same direction, be equal in magnitudes
and opposite in phase. Short pulses make those conditions
impossible.

In your above pulse example, there is no interference at
the impedance discontinuity and therefore a Z0-match doesn't
even exist. A Z0-match depends upon a steady-state supply
of RF waves.

A Z0-match at the input of a tuner works exactly like the
1/4WL thin-film anti-reflected glass coating. If one sends
a 1/2WL pulse of light at that piece of glass, there will
be reflections. Anti-reflective glass depends upon a
steady-state supply of light waves. One of the cancellation
components is 180 degrees older than the other one.

Let's return to the Signal Generators equipped with Circulators
and Loads (SGCL). Would you agree that the feedline contains
300 joules in the following example?

200W SGCL----one second long lossless feedline----100W SGCL
200W-- --100W
--
73, Cecil http://www.qsl.net/w5dxp